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COLUMBIA MANAGEMENT.                          Columbia Management Services, Inc.
PO Box 8081
Boston, MA 02266-8081

April 25, 2006

Dear Columbia Young Investor Fund Shareholder,

At Columbia Management, we periodically evaluate our mutual fund offerings as
part of a broader effort to best address the needs of fund shareholders. As a
result of that review, management has proposed mergers of several of our funds,
including a merger of Columbia Young Investor Fund into Columbia Strategic
Investor Fund. That proposal has been approved by the funds' Board of Trustees
and is subject to shareholder approval at a special meeting scheduled for
September 6, 2006. A supplement to your prospectus announcing the proposed
merger is enclosed.

In approving the merger, the Trustees of your fund considered, among other
things, the similarity of the funds' investment strategies and objectives, the
fact that the funds are managed by the same portfolio management team, and
opportunities for expense savings.

As a shareholder of the fund you can expect to receive in July a
prospectus/proxy statement for the shareholder meeting. We urge you to review
that document carefully for details of the proposed merger, and to complete and
return your proxy ballot. The merger is expected to be tax-free for federal
income tax purposes.

If approved by shareholders, the merger is tentatively scheduled for mid to late
September 2006; Columbia Young Investor Fund will remain open for additional
purchases through the close of business on the day of the merger.

We thank you for investing in Columbia Funds and look forward to serving your
investment needs for many years to come. If you have any questions, please
contact your financial advisor or a customer service representative at
800.345.6611.

Sincerely,

Christopher L. Wilson
Head of Mutual Funds, Columbia Management

PLEASE CONSIDER THE OBJECTIVES, RISKS, CHARGES AND EXPENSES OF ANY COLUMBIA FUND
CAREFULLY BEFORE INVESTING. THE FOREGOING IS NOT AN OFFER TO SELL, NOR A
SOLICITATION OF AN OFFER TO BUY, SHARES OF COLUMBIA STRATEGIC INVESTOR FUND, NOR
IS IT A SOLICITATION OF ANY PROXY. FOR MORE INFORMATION REGARDING COLUMBIA
STRATEGIC INVESTOR FUND, OR TO RECEIVE A FREE COPY OF A PROSPECTUS/PROXY
STATEMENT RELATING TO THE PROPOSED MERGER ONCE A REGISTRATION STATEMENT RELATING
TO THE PROPOSED MERGER HAS BEEN FILED WITH THE SECURITIES AND EXCHANGE
COMMISSION AND BECOME EFFECTIVE, PLEASE CALL 1-800-345-6611 OR VISIT THE FUND'S
WEBSITE AT WWW.COLUMBIAFUNDS.COM. THE PROSPECTUS/PROXY STATEMENT (WHEN
AVAILABLE) WILL CONTAIN IMPORTANT INFORMATION ABOUT FEES, EXPENSES AND RISK
CONSIDERATIONS. THE PROSPECTUS/PROXY STATEMENT WILL ALSO BE AVAILABLE FOR FREE
ON THE SECURITIES AND EXCHANGE COMMISSION'S WEBSITE (WWW.SEC.GOV). PLEASE READ
THE PROSPECTUS/PROXY STATEMENT CAREFULLY BEFORE MAKING ANY INVESTMENT DECISIONS.

Columbia Management is the primary investment management division of Bank of
America Corporation. Columbia Management entities furnish investment management
services and advise institutional and mutual fund portfolios. Columbia Funds and
CMG Funds are distributed by COLUMBIA MANAGEMENT DISTRIBUTORS, INC., member NASD
and SIPC. Columbia Management Distributors, Inc. is part of Columbia Management
and an affiliate of Bank of America Corporation.

                                                              INT-47/109655-0406

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  NOT FDIC        MAY LOSE VALUE
  INSURED    ------------------------
                NO BANK GUARANTEE
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